Authentication And Wep Encryption; Wired Equivalent Privacy (Wep) - NETGEAR MA401 Reference Manual

Reference Guide for the Model MA401 802.11b Wireless PC Card
An SSID is a thirty-two character (maximum) alphanumeric key identifying the
wireless local area network. Some vendors refer to the SSID as network name. For
the wireless devices in a network to communicate with each other, all devices
must be configured with the same SSID.

Authentication and WEP Encryption

The absence of a physical connection between nodes makes the wireless links
vulnerable to eavesdropping and information theft. To provide certain level of
security, the IEEE 802.11 standard defines two types of authentication methods:
• Open System -- Open System authentication is a null algorithm which
requires an system identifier but does not encrypt the wireless data. With
Open System authentication, a wireless PC can join any network merely by
providing the SSID and receive any messages that are not encrypted.
• Shared Key -- Shared Key authentication is an algorithm where both the
transmitting node and the receiving node share an authentication key to
perform a checksum on the original message. With Shared Key
authentication, only those PCs that possess the correct authentication key can
join the network.
By default, IEEE 802.11 wireless devices operate in open system network mode.
That is, they do not encrypt the data being transmitted over the wireless network.

Wired Equivalent Privacy (WEP)

Wired Equivalent Privacy (WEP) data encryption is utilized when the wireless
nodes or access points are configured to operate in Shared Key authentication
mode. There are two shared key methods implemented in most commercially
available products, 64-bit and 128-bit WEP data encryption.
The 64-bit WEP data encryption method, allows for a five-character (40-bit)
input. Additionally, 24 factory-set bits are added to the forty-bit input to generate
a 64-bit encryption key. The 24 factory-set bits are not user-configurable. This
encryption key will be used to encrypt/decrypt all data transmitted via the wireless
interface. Some vendors refer to the 64-bit WEP data encryption as 40-bit WEP
data encryption since the user-configurable portion of the encryption key is 40 bits
wide.
802.11b Wireless Networking Basics B-3